Van Es J H, Raaphorst F M, van Tol M J, Meyling F H, Logtenberg T
Department of Immunology, University Hospital Utrecht, The Netherlands.
J Immunol. 1993 Jan 1;150(1):161-8.
We have developed a mAb (JE-6) that recognizes an Id encoded by the most JH-proximal human VH gene segment (VH6) in or near germ-line configuration. This mAb was used to determine the frequency of Id JE6+ B cells in large collections of monoclonal EBV-transformed and short term B cell lines derived from fetal, neonatal, and adult lymphoid tissues. Moreover, we investigated the presence of Id JE-6+ Ig in sera from neonates and adults and determined the (auto)antigen binding properties of VH6-encoded IgM mAb. We detected a fivefold overrepresentation of VH6-expressing IgM producing B cells in fetal tissues, cord blood, and adult bone marrow relative to adult blood. In cord blood, but not in adult blood sera, germ-line VH6-encoded IgM molecules were readily detectable. IgM secreted by VH6-expressing B cell clones displayed highly conserved and virtually identical autoantigen binding properties, independent of the length and composition of the IgH chain CDR3 region and L chain isotype. Collectively, these results suggest that the VH6 gene and the antibodies it encodes play an important role in early human ontogeny.
我们研发了一种单克隆抗体（JE-6），它能识别由种系构型中或其附近最靠近JH的人类VH基因片段（VH6）编码的独特型。该单克隆抗体用于确定源自胎儿、新生儿和成人淋巴组织的大量单克隆EB病毒转化的短期B细胞系中独特型JE6+B细胞的频率。此外，我们研究了新生儿和成人血清中独特型JE-6+Ig的存在情况，并确定了VH6编码的IgM单克隆抗体的（自身）抗原结合特性。我们检测到，相对于成人血液，胎儿组织、脐带血和成人骨髓中表达VH6的产生IgM的B细胞数量超5倍。在脐带血而非成人血清中，种系VH6编码的IgM分子易于检测到。表达VH6的B细胞克隆分泌的IgM显示出高度保守且几乎相同的自身抗原结合特性，与IgH链CDR3区域的长度和组成以及轻链同种型无关。总体而言，这些结果表明VH6基因及其编码的抗体在人类早期个体发育中起重要作用。
